671381961 has 8 divisors (see below), whose sum is σ = 896896224. Its totient is φ = 446727840.

The previous prime is 671381957. The next prime is 671381993. The reversal of 671381961 is 169183176.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 671381961 - 2² = 671381957 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (671381941) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 213211 + ... + 216336.

It is an arithmetic number, because the mean of its divisors is an integer number (112112028).

Almost surely, 2^671381961 is an apocalyptic number.

It is an amenable number.

671381961 is a deficient number, since it is larger than the sum of its proper divisors (225514263).

671381961 is a wasteful number, since it uses less digits than its factorization.

671381961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430071.

The product of its digits is 54432, while the sum is 42.

The square root of 671381961 is about 25911.0393654905. The cubic root of 671381961 is about 875.6352224376.

The spelling of 671381961 in words is "six hundred seventy-one million, three hundred eighty-one thousand, nine hundred sixty-one".